Dendranthema plant named ‘Snowy Igloo’

ABSTRACT

A new and distinct cultivar of  Dendranthema  plant named ‘Snowy Igloo’, characterized by its upright, outwardly spreading and uniformly mounded to almost spherical plant habit; freely branching habit; dense and full plant form; uniform and freely flowering habit; decorative-type inflorescences; white-colored ray florets; natural season flowering occurs about September 13 to 23 in Pennsylvania; and good garden performance and winter hardiness.

Botanical designation: Dendranthema×morifolium.

Cultivar denomination: ‘SNOWY IGLOO’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct Dendranthema plant,botanically known as Chrysanthemum×morifolium, commercially grown as aperennial garden-type Dendranthema plant, and hereinafter referred to bythe cultivar name ‘Snowy Igloo’.

The new Dendranthema is the product of a planned breeding programconducted by the Inventors in Bogota, Colombia and Smoketown, Pa. Theobjective of the breeding program is to create new perennial garden-typeDendranthema plants having uniformly mounding plant habit,inflorescences with desirable inflorescence forms, attractive ray anddisc floret shapes and colors, winter hardiness and good gardenperformance.

The new Dendranthema plant originated from a cross-pollination made bythe Inventors in September, 2008, in Bogota, Colombia ofChrysanthemum×morifolium ‘Frosty Yoigloo’, disclosed in U.S. Plant Pat.No. 20,251, as the female, or seed, parent with a proprietary selectionof Chrysanthemum×morifolium identified as code number H6643, notpatented, as the male, or pollen, parent. The new Dendranthema plant wasdiscovered and selected by the Inventors as a single flowering plantwithin the progeny of the stated cross-pollination in a controlledgreenhouse environment in Smoketown, Pa. on Sep. 28, 2009.

Asexual reproduction of the new Dendranthema plant by vegetativecuttings was first conducted in a controlled greenhouse environment inSmoketown, Pa. in March, 2010 and such asexual propagation has shownthat the unique features of this new Dendranthema plant are stable andreproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Dendranthema have not been observed under all possiblecombinations of environmental conditions and cultural practices. Thephenotype may vary somewhat with variations in environmental conditionssuch as temperature, daylength and light intensity, without, however,any variance in genotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘Snowy Igloo’. These characteristics incombination distinguish ‘Snowy Igloo’ as a new and distinct garden-typeDendranthema plant:

-   -   1. Upright, outwardly spreading and uniformly mounded to almost        spherical plant habit.    -   2. Freely branching habit; dense and full plant form.    -   3. Uniform and freely flowering habit.    -   4. Decorative-type inflorescences.    -   5. White-colored ray florets.    -   6. Natural season flowering occurs about September 13 to 23 in        Pennsylvania.    -   7. Good garden performance and winter hardiness.

In side-by-side comparisons, plants of the new Dendranthema differ fromplants of the female parent, ‘Frosty Yoigloo’ primarily in plant size asplants of the new Dendranthema are larger than plants of ‘FrostyYoigloo’. In addition, under low night temperatures conditions, plantsof the new Dendranthema and ‘Frosty Yoigloo’ differ in ray flower coloras plants of ‘Frosty Yoigloo’ will “pink” whereas plants of the newDendranthema will retain their white ray floret coloration.

In side-by-side comparisons, plants of the new Dendranthema differprimarily from plants of the male parent selection in the followingcharacteristics:

-   -   1. Plants of the new Dendranthema are larger than plants of the        male parent selection.    -   2. Plants of the new Dendranthema flower earlier than plants of        the male parent selection.    -   3. Inflorescences of plants of the new Dendranthema have fewer        disc florets than inflorescences of plants of the male parent        selection.    -   4. Plants of the new Dendranthema and the male parent selection        differ in ray floret color as plants of the male parent        selection have golden yellow-colored ray florets.

Plants of the new Dendranthema can be compared to plants ofChrysanthemum×morifolium ‘Icicle Igloo’, disclosed in U.S. Plant patentapplication Ser. No. 13/998,708. In side-by-side comparisons, plants ofthe new Dendranthema differ from plants of ‘Icicle Igloo’ in thefollowing characteristics:

-   -   1. Plants of the new Dendranthema are larger than plants of        ‘Icicle Igloo’.    -   2. Plants of the new Dendranthema have decorative-type        inflorescences whereas plants of ‘Icicle Igloo’ have daisy-type        inflorescences.    -   3. Plants of the new Dendranthema and ‘Icicle Igloo’ differ        slightly in developing ray floret color.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying photographs illustrate the overall appearance of thenew Dendranthema showing the colors as true as it is reasonably possibleto obtain in colored reproductions of this type. Colors in thephotographs may differ slightly from the color values cited in thedetailed botanical description which accurately describe the colors ofthe new Dendranthema plant.

The photograph on the first sheet comprises a side perspective view of atypical flowering plant of ‘Snowy Igloo’ grown in a container.

The photograph on the second sheet is a close-up view of a typicalflowering plant of ‘Snowy Igloo’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations andmeasurements describe plants grown during the early autumn in 25-cmcontainers in a polyethylene-covered greenhouse in Lancaster, Pa. andunder cultural practices typical of commercial garden-type Dendranthemaproduction. During the production of the plants, day temperaturesaveraged 26.7° C. and night temperatures ranged from 15.6° C. to 18.3°C. Plants were five months old when the photographs and description weretaken. In the following description, color references are made to TheRoyal Horticultural Society Colour Chart, 2007 Edition, except wheregeneral terms of ordinary dictionary significance are used.

-   Botanical classification: Chrysanthemum×morifolium ‘Snowy Igloo’.-   Parentage:    -   -   Female, or seed, parent.—Chrysanthemum×morifolium ‘Frosty            Yoigloo’, disclosed in U.S. Plant Pat. No. 20,251.        -   Male, or pollen, parent.—Proprietary selection of            Chrysanthemum×morifolium identified as code number H6643,            not patented.-   Propagation:    -   -   Type.—Terminal vegetative cuttings.        -   Time to produce a rooted young plant.—About two weeks.        -   Root description.—Fine, fibrous; white in color.        -   Rooting habit.—Freely branching, dense.-   Plant description:    -   -   Plant and growth habit.—Perennial garden-type Dendranthema            plant with decorative-type inflorescences; upright,            outwardly spreading and uniformly mounding to almost            spherical plant habit; strong and vigorous growth habit.        -   Branching habit.—Freely branching habit, about primary            lateral branches developing at potentially every node, each            primary lateral with multiple secondary and tertiary            branches; dense and full plant form; pinching is not            required.        -   Plant height.—About 37 cm.        -   Plant width.—About 61.5 cm.        -   Lateral branches.—Length: About 31 cm. Diameter: About 3 mm.            Internode length: About 1.5 cm. Strength: Strong. Texture:            Pubescent, minute; longitudinally ridged. Color: Close to            146A.        -   Leaves.—Arrangement: Alternate, simple. Length: About            3.3 cm. Width: About 2.7 cm. Apex: Cuspidate. Base:            Truncate. Margin: Palmately lobed, sinuses between lateral            lobes mostly parallel to divergent. Texture, upper surface:            Smooth, glabrous. Texture, lower surface: Pubescent, minute;            veins prominent on lower surface. Venation pattern: Pinnate.            Color: Developing and fully expanded leaves, upper surface:            Close to N137A; venation, close to 137A. Developing and            fully expanded leaves, lower surface: Close to 137B;            venation, close to 146A to 146B. Petioles: Length: About            1.1 cm. Diameter: About 2 mm. Texture, upper surface:            Smooth, glabrous. Texture, lower surface: Pubescent; minute.            Color, upper surface: Close to N137A. Color, lower surface:            Close to 137B.-   Inflorescence description:    -   -   Type and arrangement.—Decorative-type inflorescence form            with elongated oblong-shaped ray florets; disc and ray            florets arranged acropetally on a capitulum; inflorescences            face mostly upright to outwardly and held above and beyond            the foliar plane on strong peduncles.        -   Fragrance.—None detected.        -   Flowering response.—Under natural season conditions, plants            flower about September 13 to 23 in Pennsylvania.        -   Postproduction longevity.—Inflorescences maintain good color            and substance for about three to six weeks on the plant            depending on temperatures; inflorescences persistent.        -   Quantity of inflorescences.—Freely flowering habit with            about five inflorescences developing per lateral branch.        -   Inflorescence buds.—Height: About 4 mm. Diameter: About            4.5 mm. Shape: Oblate to spherical. Color: Close to N137A.        -   Inflorescence size.—Diameter: About 2.6 cm. Depth (height):            About 1.25 cm. Disc diameter: About 2 mm. Receptacle            diameter: About 4 mm. Receptacle height: About 4 mm.        -   Receptacle color.—Close to 144A to 144B.        -   Ray florets.—Quantity and arrangement: About 132 ray florets            develop per inflorescence and arranged in numerous whorls.            Length: About 1.4 cm. Width: About 4 mm. Shape: Elongated            oblong. Apex: Emarginate. Base: Attenuate and then fused            into a short tube. Margin: Entire. Orientation: Initially            upright, then arching outwardly. Texture, upper and lower            surfaces: Smooth, glabrous; velvety; longitudinally ribbed.            Color: When opening, upper surface: Close to 6D; at the            base, close to 144A. When opening, lower surface: Close to            6D. Fully opened, upper surface: Close to NN155D; at the            base, close to 144A; color does not change with development.            Fully opened, lower surface: Close to NN155D; color does not            fade with development.        -   Disc florets.—Quantity and arrangement: None to about twelve            fused disc florets develop per inflorescence and massed at            the center of the capitulum; inconspicuous. Length: About            4 mm. Diameter: About 1 mm. Shape: Tubular, elongated. Apex:            Five-pointed. Texture, inner and outer surfaces: Smooth,            glabrous. Color, mature: Apex: Close to 12A. Mid-section:            Close to 144B to 144C. Base: Close to NN155D.        -   Phyllaries.—Quantity and arrangement: About 18 phyllaries            develop per inflorescence and arranged in about two to three            whorls. Length: About 5 mm. Width: About 2.5 mm. Shape:            Lanceolate. Apex: Acute. Base: Truncate, fused. Margin:            Entire; membraneous. Texture, upper surface: Smooth,            glabrous. Texture, lower surface: Pubescent, minute. Color,            upper and lower surfaces: Close to 137A.        -   Peduncles.—Length, terminal peduncle: About 2.4 cm. Length,            fourth peduncle: About 3.6 cm. Diameter, terminal peduncle:            About 1.5 mm. Angle: Mostly upright or curving upright.            Strength: Strong, wiry. Texture: Pubescent; minute. Color:            Close to 146A.        -   Reproductive organs.—Androecium (present on disc florets            only): Stamen number: Five per floret. Filament length:            About 4 mm. Filament color: Close to 150D. Anther length:            Less than 1 mm. Anther shape: Narrowly oblong. Anther color:            Close to 12A. Pollen amount: None observed. Gynoecium            (present on ray and disc florets): Pistil length: About            4 mm. Stigma shape: Bi-parted. Stigma color: Close to 6A.            Style length: About 3.5 mm. Style color: Close to 154D.            Ovary color: Close to 144A.        -   Seeds and fruits.—Seed and fruit production has not been            observed on plants of the new Dendranthema.-   Disease & pest resistance: Resistance to pathogens and pests common    to Dendranthema plants has not been observed on plants of the new    Dendranthema grown under commercial production conditions.-   Garden performance & temperature tolerance: Plants of the new    Dendranthema have demonstrated excellent garden performance, are    hardy to USDA Zone 5 and tolerate high temperatures about 37.8° C.

It is claimed:
 1. A new and distinct Dendranthema plant named ‘SnowyIgloo’ as illustrated and described.